package org.iteye.bbjava.frame.work.utils;

/**
 * Copyright (c) 2005-2009 springside.org.cn
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * 
 * $Id$
 */

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.lang.StringEscapeUtils;

/**
 * 各种格式的编码加码工具类.
 * 
 * 集成Commons-Codec,Commons-Lang及JDK提供的编解码方法.
 * 
 * @author calvin
 */
public class EncodeUtils {

        private static final String DEFAULT_URL_ENCODING = "UTF-8";

        /**
         * Hex编码.
         */
        public static String hexEncode(byte[] input) {
                return Hex.encodeHexString(input);
        }

        /**
         * Hex解码.
         */
        public static byte[] hexDecode(String input) {
                try {
                        return Hex.decodeHex(input.toCharArray());
                } catch (DecoderException e) {
                        throw new IllegalStateException("Hex Decoder exception", e);
                }
        }

        /**
         * Base64编码.
         */
        public static String base64Encode(byte[] input) {
                return new String(Base64.encodeBase64(input));
        }

        /**
         * Base64编码, URL安全(将Base64中的URL非法字符如+,/=转为其他字符, 见RFC3548).
         */
        public static String base64UrlSafeEncode(byte[] input) {
                return Base64.encodeBase64URLSafeString(input);
        }

        /**
         * Base64解码.
         */
        public static byte[] base64Decode(String input) {
                return Base64.decodeBase64(input);
        }

        /**
         * URL 编码, Encode默认为UTF-8. 
         */
        public static String urlEncode(String input) {
                return urlEncode(input, DEFAULT_URL_ENCODING);
        }

        /**
         * URL 编码.
         */
        public static String urlEncode(String input, String encoding) {
                try {
                        return URLEncoder.encode(input, encoding);
                } catch (UnsupportedEncodingException e) {
                        throw new IllegalArgumentException("Unsupported Encoding Exception", e);
                }
        }

        /**
         * URL 解码, Encode默认为UTF-8. 
         */
        public static String urlDecode(String input) {
                return urlDecode(input, DEFAULT_URL_ENCODING);
        }

        /**
         * URL 解码.
         */
        public static String urlDecode(String input, String encoding) {
                try {
                        return URLDecoder.decode(input, encoding);
                } catch (UnsupportedEncodingException e) {
                        throw new IllegalArgumentException("Unsupported Encoding Exception", e);
                }
        }

        /**
         * Html 转码.
         */
        public static String htmlEscape(String html) {
                return StringEscapeUtils.escapeHtml(html);
        }

        /**
         * Html 解码.
         */
        public static String htmlUnescape(String htmlEscaped) {
                return StringEscapeUtils.unescapeHtml(htmlEscaped);
        }

        /**
         * Xml 转码.
         */
        public static String xmlEscape(String xml) {
                return StringEscapeUtils.escapeXml(xml);
        }

        /**
         * Xml 解码.
         */
        public static String xmlUnescape(String xmlEscaped) {
                return StringEscapeUtils.unescapeXml(xmlEscaped);
        }
}